Amanda M. Kelley

Modafinil as a replacement for dextroamphetamine for sustaining alertness in military helicopter pilots

INTRODUCTION Successful military aviation operations depend on maintaining continuous day-night operations. Stimulants are easy to use and popular for sustaining performance because their utility is not dependent upon environmental or scheduling modifications. Dextroamphetamine is authorized for use by the aircrews of all U.S. military services, but its potential for abuse and subsequent addiction is of aeromedical concern. Finding an alternative stimulant, such as modafinil, that displays a low affinity for dopamine uptake binding sites would prove extremely beneficial. This study sought to establish the efficacy and safety of modafinil during actual flying operations, thus providing the operational validity desired to approve the use of modafinil for helicopter flight operations. METHODS During two, 40-h periods of sustained wakefulness, 18 helicopter pilots (17 men, 1 woman, mean years of age = 29.5) each completed 15 flights and other evaluations, during which they received 2 of 3 experimental conditions: 3 doses at 4-h intervals of modafinil (100 mg), dextroamphetamine (5 mg), or placebo. RESULTS Statistical results showed that modafinil, like dextroamphetamine, maintained alertness, feelings of well-being, cognitive function, judgment, risk perception, and situation awareness of sleep-deprived aviators consistently better than placebo and without side effects of aeromedical concern. DISCUSSION Like previous research, this study strongly suggests that both drugs can maintain acceptable levels of mood and performance during sleep deprivation. The results also confirm that modafinil is well tolerated and appears to be a good alternative to dextroamphetamine for countering the debilitating mood and cognitive effects of sleep loss during sustained operations.

Cognition enhancement by modafinil: a meta-analysis.

INTRODUCTION Currently, there are a number of pharmaceuticals available that have potential to enhance cognitive functioning, some of which may ultimately be considered for such use in military operations. Some drugs with potential for cognition enhancement have already been studied for use in military operations specific to their primary effect in sleep regulation (i.e., dextroamphetamine, modafinil, caffeine). There is considerable information available on many of these drugs. However, considerations for military appropriateness must be based on proficient research (e.g., randomly controlled trial design). METHODS A meta-analysis was conducted to summarize the current state of knowledge of these potentially cognition-enhancing drugs. The analysis only included studies which met inclusion criteria relevant to military research. RESULTS The results of the literature review reveal a gap in research of the enhancement properties of the drugs of interest. The results yielded three studies (all of which studied modafinil) that met the criteria. The meta-analysis of these three studies revealed a relatively weak pooled effect of modafinil on some aspects of cognitive performance in normal, rested adults. DISCUSSION While the results of this study support the efficacy of modafinil, the main finding is the large literature gap evaluating the short- and long-term effects of these drugs in healthy adults.

Tactile Cues for Orienting Pilots During Hover Over Moving Targets

INTRODUCTION Providing information via the tactile sensory system allows the pilot to increase awareness without further taxing the visual and auditory perceptual systems. In this study, tactile cues were presented to pilots for target orientation during a simulated helicopter extraction over a moving target. The efficacy of the cues provided by the tactile system was assessed under various conditions (rested vs. fatigued, clear vs. degraded visual environment). METHODS This study employed a mixed-model 2(4) factorial design, including one between-subjects variable (training amount: minimal, additional) and three within-subjects variables (state: rested, fatigued; visual environment: clear, degraded; tactile cue belt: active, inactive). Across 2 d under the 4 test conditions, 16 UH-60 rated, healthy aviators completed 8 sessions of 10-min stabilized hovering maneuvers over a moving target. All flights were conducted in a UH-60 flight simulator. RESULTS Subjects were able to stay closer to the target when the tactile cuing system was active (M = 31.14 ft, SE = 3.17 ft) vs. inactive (M = 36.33 ft, SE = 2.84 ft). Likewise, subjects rated their situation awareness as greater when the tactile system was active vs. inactive. DISCUSSION The results support the efficacy of the tactile system in providing directional cues for maintaining pilot performance during a hover maneuver over a moving target.

Reported Back Pain in Army Aircrew in Relation to Airframe, Gender, Age, and Experience.

INTRODUCTION Back pain has remained an issue of significance among aircraft crewmembers for decades, occurring in the majority of military helicopter pilots with potential deleterious effects on performance, safety, and operational readiness. This exploratory, correlational survey study was designed to evaluate the presence of patterns and relationships that may require further examination to understand causal factors. METHODS The study population consisted of U.S. Army aviation crewmembers. Subjects (467) completed an anonymous survey, including questions regarding demographics, airframes, experience, pain history and severity, ergonomics, mitigation strategies, and duty limitations. RESULTS Overall, 84.6% of participants reported back pain at some time during their flying career, with 77.8% reporting back pain in the last calendar year. Age was found to significantly correlate with earlier time to pain during flight, higher pain rating after flight, and occurrence of grounding. A stepwise linear regression model was used to explore the relationships between age, flight hours, and years of aviation experience, demonstrating age to be the significant variable accounting for the observed variance. Aircrew reported wear of combat-related survival equipment and poor lumbar support to be the most notable contributors. DISCUSSION Back pain rates were consistent with previous studies. The relationship of age to back pain in this study may highlight unique pathophysiological pathways that should be further investigated within an occupational context to better understand the etiologic role. Enhanced seated lumbar support and combat-related survival equipment remain relatively low-cost/high-yield topics worthy of further investigation for exploiting efficient means to improve health, safety, and operational performance.Kelley AM, MacDonnell J, Grigley D, Campbell J, Gaydos SJ. Reported back pain in army aircrew in relation to airframe, gender, age, and experience. Aerosp Med Hum Perform. 2017; 88(2):96-103.

A Materiel Solution to Aircraft Upset

The U.S. Army, together with NASA and the U.S. Navy, have developed and flight tested a tactile cueing display that addresses several of the causes of aircraft upset. The Tactile Situation Awareness System (TSAS) continuously presents critical flight parameters providing intuitive situation awareness, permitting aircrew to perform the basic skills of aviating non-visually and with more “automaticity,” whilst simultaneously attending to other tasks visually. Five U.S. Army accident investigators, who were provided demonstrations of TSAS technology in a motion-based helicopter simulator, independently assessed 330 Class A mishaps (loss of life or greater than 2 Mill damage) from 1992 to 2010. The investigators determined that 24% of Army aviation Class A mishaps could have been avoided with TSAS technology.

Tactile cues in continuous operations: a preliminary study.

INTRODUCTION Research has shown that tactile displays are an effective tool for augmenting spatial orientation and situation awareness information provided to aircraft operators. The tactile situation awareness system (TSAS) has been shown to improve flight performance in conditions of degraded visual environments and to safely maintain performance during hover over moving targets. The potential for the user to adapt and habituate to the stimulus of tactile display systems has not yet been investigated. METHODS Four UH-60 current, rated aviators (all male) participated in the pilot study. Subjects completed four consecutive iterations of a 3-h flight profile consisting of 10 maneuvers, totaling 12 h of continuous flight. Flight performance, tactor information, responses to a discomfort questionnaire, and ratings of fatigue symptoms were recorded. RESULTS The independent variable in all analyses was session (four levels). The results showed that performance per maneuver and proportion of stimulus cues (measure of response to cues) per maneuver were consistent across sessions using independent-samples Kruskal-Wallis tests. DISCUSSION The findings of this preliminary assessment support the use of tactile displays (consistent with parameters of TSAS) in continuous operations since performance and proportion of stimulus cues presented was consistent over a period of 12 h. In conclusion, the system will require further experimental testing, but these preliminary findings do not suggest performance or response to be affected by any adaptation or habituation to the stimulus.

Computerized Tests of Team Performance and Crew Coordination Suitable for Military/Aviation Settings

INTRODUCTION The coordination of team effort on shared tasks is an area of inquiry. A number of tests of team performance in challenging environments have been developed without comparison or standardization. This article provides a systematic review of the most accessible and usable low-to-medium fidelity computerized tests of team performance and determines which are most applicable to military- and aviation-relevant research, such as studies of group command, control, communication, and crew coordination. METHODS A search was conducted to identify computerized measures of team performance. In addition to extensive literature searches (DTIC, Psychinfo, PubMed), the authors reached out to team performance researchers at conferences and through electronic communication. RESULTS Identified were 57 potential tests according to 6 specific selection criteria (e.g., the requirement for automated collection of team performance and coordination processes, the use of military-relevant scenarios). The following seven tests (listed alphabetically) were considered most suitable for military needs: Agent Enabled Decision Group Environment (AEDGE), C3Conflict, the C3 (Command, Control, & Communications) Interactive Task for Identifying Emerging Situations (NeoCITIES), Distributed Dynamic Decision Making (DDD), Duo Wondrous Original Method Basic Awareness/Airmanship Test (DuoWOMBAT), the Leader Development Simulator (LDS), and the Planning Task for Teams (PLATT). Strengths and weaknesses of these tests are described and recommendations offered to help researchers identify the test most suitable for their particular needs. DISCUSSION Adoption of a few standard computerized test batteries to study team performance would facilitate the evaluation of interventions intended to enhance group performance in multiple challenging military and aerospace operational environments.Lawson BD, Britt TW, Kelley AM, Athy JR, Legan SM. Computerized tests of team performance and crew coordination suitable for military/aviation settings. Aerosp Med Hum Perform. 2017; 88(8):722-729.

Evaluation of the Military Functional Assessment Program: Preliminary Assessment of the Construct Validity Using an Archived Database of Clinical Data

Background:Several important factors must be considered when deciding to return a soldier to duty after a traumatic brain injury (TBI). Premature return increases risk for not only second-impact syndrome during the acute phase but also permanent changes from repetitive concussions. Thus, there is a critical need for return-to-duty (RTD) assessment criteria that encompass the spectrum of injury and disease experienced by US soldiers, particularly TBI. Objectives:To provide evidence-based standards to eventually serve as criteria for operational competence and performance of a soldier after injury. Specifically, the relationships between clinical assessments and novel military-specific tasks were evaluated. Method:Exploratory analyses (including nonparametric tests and Spearman rank correlations) of an archived database. Participants:A total of 79 patients with TBI who participated in an RTD assessment program at a US Army rehabilitation and recovery center. Main Measures:Military Functional Assessment Program (to determine a soldiers operational competence and performance after TBI) tasks; Dizziness Handicap Inventory; Dynamic Visual Acuity (vestibular function); Sensory Organization Test (postural control); Repeatable Battery for the Assessment of Neuropsychological Status (neuropsychological screening test); Beck Depression Inventory-II; Beck Anxiety Inventory; Comprehensive Trail Making Test (visual search and sequencing); posttraumatic stress disorder checklist military version; Alcohol Use Disorders Identification Test; Epworth Sleepiness Scale; Patient Health Questionnaire; and Military Acute Concussion Evaluation. Results:Selected military operational assessment tasks correlated significantly with clinical measures of vestibular function, psychological well-being, and cognitive function. Differences on occupational therapy assessments, a concussion screening tool, and a self-report health questionnaire were seen between those who passed and those who failed the RTD assessment. Specifically, those who passed the RTD assessment scored more favorably on these clinical assessments. Conclusions:This study demonstrated convergent validity between Military Functional Assessment Program tasks and clinical assessment scores. The Military Functional Assessment Program shows promise for augmenting decision making related to RTD and soldier skills. Additional research is needed to determine the effectiveness of this program in predicting RTD success.

A countermeasure for loss of situation awareness: Transitioning from the laboratory to the aircraft

Loss of situation awareness (SA) is a major contributor to aircraft mishaps. This paper describes a technological (display) countermeasure for loss of situation awareness in flight and considers its key remaining transition challenges. The display countermeasure is a tactile situation awareness system (TSAS) that provides cues concerning aircraft motion. For example, if a helicopter drifts upwards, forwards, or downwards away from its desired hover, the pilot would feel a vibrotactile pulse on top of his/her shoulders, the front of his/her torso, or beneath his/her buttocks, respectively. The key challenge remaining for the TSAS is to transition from the research laboratory science and technology (S&T) setting to routine use aboard manned aircraft, which requires extensive flight testing. We present research evidence supporting the utility of the cues provided by TSAS, the safety benefits of TSAS, and the robustness of TSAS under demanding conditions relevant to flight. However, the research setting differs greatly from the operational setting it serves. Therefore, we conclude by sharing seven practical technology transition lessons we have learned from our efforts to transition TSAS from S&T to the very different world of flight operations. We discuss how the differing procedures, standards, timelines, priorities, incentives, and expectations of scientific versus flight testing raise significant challenges to the efficient transition of new technological inventions to the aircraft. Our hope is that describing our ongoing efforts with TSAS will aid similar display technology transition efforts and provide inventors information that could foster government innovation and implementation.

Human Factors to Consider During the Early Development and Dissemination of New Displays to Improve Spatial Orientation and Situation Awareness

When a new technology is contemplated to enhance situation awareness (SA), thought must be given to designing, prototyping, and demonstrating it to enhance usability and acceptance. The focus during this process is typically upon the end-user. We introduce three SA-enhancing displays (designed to avoid spatial disorientation (SD), falling, and collisions, respectively) and describe the typical end-users of such displays. We then argue for a wider consideration of human factors (HF) that includes the needs of those in the entire human chain of technology development before the final end-users. We intend to show how solving problems associated with the early development and refinement of new technologies requires a consideration of multiple types of “users”. Consideration of only the end-user is not sufficient to ensure technology acceptance in any of the three case studies described in this report. Everyone in the chain of technology development must be considered a user.